9results about How to "Suppress overvoltage" patented technology

The application discloses a full-automatic variable-distance flexible grabbing system and a control method thereof, converts mechanical adjustment of X-axis, Z-axis and Y-axis into electrical parameter adjustment, and provides two control methods which are special for a clamping module of the full-automatic system and are used for servo drivers of the clamping module, namely, a software multi-circle backup is used to replace an internal battery of an encoder, and cross-rolling verification is combined, so that the servo driver of the clamping module can directly enter a clamping ready state without returning to an original point mechanically after being powered on; and a weak magnetic control algorithm is used to suppress reverse electromotive force from a source, replace passive protection devices on a sensor signal line, and guarantee that multi-sensor AND fusion determination logic is continuously reliable in a full-speed section. The application eliminates two delay sources of initialization waiting and sensor failure, and realizes a complete closed loop from structure to control, and releases a formula to zero-second transformation.

The application discloses a photovoltaic grid-connected system and an alternating current fault ride-through method and device thereof, and comprises a plurality of photovoltaic arrays, a plurality of photovoltaic grid-connected inverters, a direct current collection line and a step-up transformer. Each photovoltaic grid-connected inverter is composed of six bridge arms, wherein each bridge arm comprises a plurality of photovoltaic sub-modules; each photovoltaic sub-module comprises a front-stage MMC converter sub-module and a rear-stage DC-DC converter. When an alternating current fault occurs in the photovoltaic grid-connected system, a hierarchical three-stage control of a photovoltaic converter stage, a bridge arm stage and a sub-module stage is combined to independently regulate the output of each photovoltaic sub-module, ensure that photovoltaic MPPT control is not completely disabled during the fault ride-through, inhibit overvoltage of the photovoltaic sub-module when the grid voltage drops, and realize the alternating current fault ride-through of the photovoltaic grid-connected system.

An anode gas diffusion layer for a water electrolysis cell includes metal fiber. The metal fiber has a section. The section constitutes a surface of the metal fiber. The section is composed of nickel. A water electrolysis cell includes an anode, a cathode, and an electrolyte membrane. The electrolyte membrane is disposed between the anode and the cathode. The anode includes the anode gas diffusion layer for the water electrolysis cell.

A kind of combined grid-friendly photovoltaic confluence system for 5G base station, including confluence unit, sensing unit, photovoltaic power generation system is accessed to direct current bus through confluence unit;Sensing unit collects distribution network voltage information and is transmitted to confluence unit in real time;Confluence unit according to distribution network voltage and direct current bus voltage, dynamically adjusts output power.Confluence unit includes: main power circuit, auxiliary power supply circuit, sampling circuit, drive circuit, control module, protection circuit, first wireless communication module.Sensing unit includes: single-chip microcomputer, wireless communication module, ac power grid power quality monitoring unit, auxiliary power supply.The utility model discloses a kind of combined grid-friendly photovoltaic confluence system for 5G base station, to be able to cope with 5G base station inside direct current bus overvoltage problem, simultaneously can according to the distribution network voltage of surrounding node, dynamically adjust power output, improve the stability of power supply system.

The application discloses a kind of coordinated control method and system for inhibiting power grid overvoltage, according to grid voltage and phase modifier steady-state displacement, construct the control strategy of reactive power source for inhibiting power grid overvoltage, in the control strategy of reactive power source, consider the voltage counter-regulation caused by the action delay of SVC, only after DC commutation failure according to grid voltage trajectory Trigger SVC coordinated control, in the case of power grid overvoltage, add phase modifier to DC reactive power compensation system, make it with original converter station filter, DC reactive power compensation capacitor coordinated as the operation of new DC reactive power compensation system, according to grid voltage situation Control phase modifier and SVC, realized that multiple types of reactive power source inhibit power grid whole process overvoltage, improve the voltage comprehensive control level of high proportion new energy DC external sending system.

The invention discloses a voltage test loop and method for state inspection of an extra-high voltage AC circuit breaker, and the test loop comprises a first voltage source which is connected in series with one end of a tested circuit breaker, and is provided with a first control switch; the second voltage source is connected in series with the other end of the tested circuit breaker, and a second control switch is arranged on the second voltage source; wherein the first control switch is used for controlling the first voltage source to apply voltage to one end of the tested circuit breaker; and the second control switch is used for applying voltage to the other end of the tested circuit breaker by the second voltage source at a specific time. According to the test loop, the first voltage source and the second voltage source are utilized, the test loop for the voltage test of the ultra-high voltage alternating-current circuit breaker for state inspection and the control method are established, and compared with a traditional voltage source test loop, the control precision is high; according to the method, overvoltage generated during breakdown of the tested circuit breaker can be suppressed by using the resistor R3, and the resistor R3 can adjust waveform parameters according to standard requirements.

The present invention relates to a closing surge suppression device for reactive compensation in the field of reactive compensation in distribution networks. The device is installed on the incoming line side of a capacitor group for reactive compensation, and includes a voltage transformer, a current sensor, a circuit breaker, a fast switch, a phase control device, and a controller. When the capacitor group needs to be put into operation, the capacitor group can be put into operation by first closing the circuit breaker, so that the surge generated when closing the circuit breaker is first suppressed by the phase control device; then the fast switch is closed to exit the phase control device, and the capacitor group remains in operation. In the case of presetting multiple protection branches, each protection branch is connected to a control device respectively, and the control device can realize automatic control by using the size of the closing surge current, so that a corresponding number of protection branches can be put into operation as needed in the process of eliminating the surge peak.

The utility model discloses an overvoltage suppression device of a steel rail potential limiting device, when a steel rail potential limiter is switched on, a direct current contactor K2 is switched on, a solid-state relay K3 is switched on, a non-polar capacitor Cs1 is charged by a 220V AC / DC charging loop, when the voltage at the two ends of the non-polar capacitor Cs1 reaches 300V, the solid-state relay K3 is switched off, and the charging process is completed within 3 seconds; when the steel rail potential limiter is switched off and a 25V voltage difference is detected between a steel rail and the ground, the control system triggers the controllable semiconductor device SCR1 and the controllable semiconductor device SCR2 to be switched on, so that a reverse current arc extinction loop is formed, and steel rail overvoltage generated when the steel rail potential limiter is switched off is suppressed; and after the capacitor is reversely charged, the controllable semiconductor device SCR1 and the controllable semiconductor device SCR2 are cut off. According to the invention, a piezoresistor or a lightning arrester is not needed, and when a line suffers from frequent overvoltage impact, the overvoltage of the steel rail can be rapidly suppressed.